This week's book giveaway is in the OCMJEA forum. We're giving away four copies of OCM Java EE 6 Enterprise Architect Exam Guide and have Paul Allen & Joseph Bambara on-line! See this thread for details.
Presumably select name from emp where ref_id=10 returns more than one row? If it does you will need to use a cursor to do this. Open a cursor and for each of your name attributes, select the next value from the sequence and insert them into emp.